1. Field of the Invention
The present invention relates to a wood type golf club head. More particularly, the present invention relates to a golf club head body having a plurality of annular flexible portions in place that increases an elastic deformation of the golf club head body.
2. Description of the Related Art
A conventional wood type golf club head typically includes a golf club head body and a striking plate connected thereto. Generally, the striking plate is made of material with high coefficient of resilience (C.O.R.) and used to strike a golf ball. The golf club head body can be selectively made of metal or nonmetal (such as carbon fiber) and used to return a striking stress to the striking plate. Structurally, the golf club head body includes a crown portion, a sole portion, a toe portion, a heel portion and a side portion to constitute a body member. By such an arrangement, the golf club head can return the striking stress to the striking plate and absorb remained vibrations while striking golf ball.
U.S. patent application Publication No. 2003/0064823 discloses a golf club head. The golf club head commonly includes a golf club head body and a striking plate. In particular, the striking plate includes an inner surface provided with annular-stepped portions that change in thickness for increasing an elastic deformation of the striking plate. As to the golf club head body, it has no corresponding structure for relatively increasing an elastic deformation of the entire golf club head.
However, the golf club head body cannot effectively return the striking stress to the striking plate due to no relative increase of the elastic deformation of the entire golf club head. Additionally, exerting a greater striking stress may cause the golf club head body to permanently deform and crack. In other words, even if the striking plate obtains excellent elasticity, it cannot provide an excellent striking ability with limited elastic deformation of the golf club head body.
Hence, there is a need for a structure of the golf club head body to improve an elastic deformation of the golf club head body for striking a golf ball. To accomplish this task, it is necessary to modify the golf club head body.
The present invention provides a golf club head body having a plurality of annular flexible portions in place that increase an elastic deformation of the golf club head body. Thereby, the annular flexible portions of the golf club head body can increase striking ability, eliminate metal fatigue and intensify strength of the golf club head in such a way to mitigate and overcome the above problem.